JP3836854B2 - Packet relay apparatus and packet relay program - Google Patents

Description

  The present invention relates to a packet relay device, a packet relay method, and a packet relay program suitable for use in relaying, for example, route information packets, and in particular, a packet relay device that can reduce the load on the destination of route information. The present invention relates to a packet relay method and a packet relay program.

  Conventionally, in packet networks, sessions are established between routers based on BGP (Border Gateway Protocol), and route information is exchanged on the sessions. Here, when exchanging route information, it is necessary to run a full mesh session between all routers in the packet network. As the number of routers increases, the number of sessions increases, which causes scalability problems. .

  Therefore, conventionally, a route reflector device as a packet relay device is provided in the packet network to solve this problem. This route reflector device is a device that relays route information between routers.

FIG. 7 is a block diagram for explaining a conventional route information distribution method using the above-described route reflector device. In the figure, the customer edge router 10 _1, the customer edge router 10 _2, the provider edge router 20 _1, the provider edge router 20 _2, the packet network having a route reflector device 30 ₁ to 30 ₄ are shown.

The customer edge router 10 ₁ and the customer edge router 10 ₂ are routers provided on the customer side and have a function of routing packets. The provider edge router 20 ₁ and the provider edge router 20 ₂ are host devices for the customer edge router 10 ₁ and the customer edge router 10 ₂ , and are provided on the provider side. The provider edge router 20 ₁ and the provider edge router 20 ₂ have a function of routing packets.

Route reflector apparatus 30 ₁ to 30 ₄ is a higher-level device for the provider edge router 20 ₁ and the provider edge router 20 _2, has a function of relaying the route information. Here, in the route reflector devices 30 ₁ to 30 ₄ , parallel redundancy is adopted by providing the route reflector device 30 ₂ and the route reflector device 30 ₃ in parallel.

In the above configuration, for example, when the route information packet 40 related to the route information to be distributed is transmitted from the provider edge router 20 ₂ , the route information packet 40 is received by the route reflector device 30 ₄ . The route reflector device 30 ₄ copies the two route information packets 40a and the route information packet 40b from the route information packet 40, and then transmits them.

The route information packet 40a is relayed to the route reflector device 30 ₂ and then received by the route reflector device 30 ₁ . On the other hand, the route information packet 40b is relayed to the route reflector device 30 ₃ and then received by the route reflector device 30 ₁ . That is, route reflector device 30 ₁ receives both the routing information packets 40a and route information packet 40b is the same content, holds.

Next, the route reflector device 301 selects _one of the route information packet 40a and the route information packet 40b as the optimum route information based on a predetermined selection criterion. In this case, assuming that the path information packet 40a is selected, route reflector device 30 ₁ transmits the path information packet 40a. Route information packet 40a is received by the provider edge router 20 _1.

As shown in FIG. 8, when a failure occurs in the route reflector device 30 ₂ , the route reflector device 30 ₁ detects the failure and then replaces the route information packet 40 a received from the route reflector device 30 _2. , as the optimal path information to the path information packet 40b received from the route reflector apparatus 30 _3, and re-transmits it to the provider edge router 20 _1. Thus, the provider edge router 20 _1, discards the path information packet 40a the previously received route information packet 40b and the optimal route information.

JP 2003-304293 A

By the way, in the conventional packet network, parallel redundancy is adopted, so that even if a failure occurs in the route reflector device 30 ₂ , the route information packet 40 _b received from the route reflector device 30 ₃ is received by the provider edge router 20 _1. Re-send to increase network reliability.

However, in the conventional packet network, there is a case where the data amount of the path information packet to be transmitted from the route reflector device 30 ₁ to the provider edge router 20 ₁ is high as several tens of thousands of paths, path information in the provider edge router 20 ₁ There has been a problem in that the load related to the process increases, which may adversely affect the execution of other protocol processes that should be performed, and may lead to the loss of route information.

  The present invention has been made in view of the above, and an object of the present invention is to provide a packet relay apparatus, a packet relay method, and a packet relay program that can reduce the load on the transmission destination of route information.

  In order to solve the above-described problems and achieve the object, the present invention provides a packet relay device that relays route information exchanged between routers in a packet network. Priority determination means for determining the priority of the route information as a first priority or a second priority lower than the first priority based on the criteria of the first priority by the priority determination means If it is determined that the route information is stored in the first storage unit, and if the second priority is determined, the storage control unit stores the route information in the second storage unit, and the first storage unit stores the route information. Transmission control means for immediately transmitting the stored route information to a destination router, and transmitting the route information stored in the second storage means at a timing that does not adversely affect the processing of the destination router; To have prepared And butterflies.

  In addition, the present invention is a packet relay method applied to a packet relay device that relays route information exchanged between routers in a packet network. When the route information to be relayed is received, the present invention is based on a predetermined criterion. A priority determination step of determining the priority of the route information as a first priority or a second priority lower than the first priority, and a case where the first priority is determined in the priority determination step The route information is stored in the first storage means, and if it is determined as the second priority, the storage control step of storing the route information in the second storage means, and the route information stored in the first storage means And a transmission control step of transmitting the route information stored in the second storage means at a timing that does not adversely affect the processing of the destination router. To do.

  The present invention is also a packet relay program applied to a packet relay device that relays route information exchanged between routers in a packet network, and when a computer receives route information to be relayed, a predetermined criterion is used. Based on the priority determination step of determining the priority of the route information as the first priority or a second priority lower than the first priority, and determining the first priority in the priority determination step If it is determined that the route information is stored in the first storage means, and the second priority is determined, the storage control step for storing the route information in the second storage means is stored in the first storage means. A transmission control step of transmitting the route information immediately to the destination router and transmitting the route information stored in the second storage means at a timing that does not adversely affect the processing of the destination router. A packet relay program for causing.

  According to the present invention, when route information to be relayed is received, the priority of the route information is determined as the first priority or the second priority lower than the first priority based on a predetermined criterion. If the first priority is determined, the path information is stored in the first storage means. If the second priority is determined, the path information is stored in the second storage means. Is immediately transmitted to the destination router, and the route information stored in the second storage means is transmitted at a timing that does not adversely affect the processing of the destination router. It is possible to reduce the load on the transmission destination.

  Embodiments of a packet relay device, a packet relay method, and a packet relay program according to the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

FIG. 1 is a block diagram showing the configuration of an embodiment according to the present invention. In the figure, portions corresponding to the respective portions in FIG. In FIG. 1, route reflector devices 100 _{1 to} 100 ₄ are provided instead of the route reflector devices 30 ₁ to 30 ₄ shown in FIG. 7.

The route reflector devices 100 _{1 to} 100 ₄ are host devices for the provider edge router 20 ₁ and the provider edge router 20 ₂ , and have a function of relaying route information. Here, in the route reflector devices 100 _{1 to} 100 ₄ , the route reflector device 100 ₂ and the route reflector device 100 ₃ are provided in parallel in the same manner as the route reflector devices 30 ₁ to 30 ₄ (see FIG. 7). Parallel redundancy is adopted.

FIG. 2 is a block diagram showing a configuration of the route reflector device 100 ₁ shown in FIG. In the route reflector device 100 ₁ shown in the figure, the packet receiving unit 101 has a function of receiving a route information packet. The packet processing unit 102 has a function of selecting a route information packet corresponding to the optimum route based on the route information packet received by the packet receiving unit 101, and a function of determining the priority of the selected route information packet. I have.

  Here, when it is determined that the priority is high (priority 1), the packet processing unit 102 stores the route information packet in the primary queue 105. On the other hand, when determining that the priority is low (priority 2), the packet processing unit 102 stores the route information packet in the secondary queue 106.

  The primary queue 105 is a storage unit that stores, in a queue structure, path information packets that are determined to have high priority (priority 1). On the other hand, the secondary queue 106 is a storage unit that stores path information packets determined to have a low priority (priority 2) in a queue structure. The route information database 103 is a database that stores route information packets received by the packet receiving unit 101.

The optimum route information database 104 is a database that stores packets that are determined as route information packets corresponding to the optimum route by the packet processing unit 102. The packet generation unit 107 has a function of generating a transmission route information packet whose destination is changed based on the route information packet stored in the primary queue 105 or the secondary queue 106. The packet transmission unit 108 has a function of transmitting the route information packet generated by the packet generation unit 107. The route reflector device 100 ₄ shown in FIG. 1 has the same configuration as the route reflector device 100 ₁ described above.

  Next, the operation of the embodiment will be described with reference to FIGS. FIG. 3 is a flowchart for explaining operations of the packet receiver 101 and the packet processor 102 shown in FIG. FIG. 4 is a flowchart for explaining operations of the packet generator 107 and the packet transmitter 108 shown in FIG. FIG. 5 is a block diagram for explaining the operation of the embodiment.

In step SA1 shown in FIG. 3, the packet processing unit 102 of the route reflector device 100 ₁ (see FIG. 2) determines whether the packet receiving unit 101 has received a route information packet or a failure has occurred. In this case, the determination result is “No” and the determination is repeated. The failure here means a failure in the route reflector device 100 ₂ or the route reflector device 100 ₃ .

In step SB1 shown in FIG. 4, the packet generation unit 107 of the route reflector device 100 ₁ determines whether or not the packet transmission unit 108 has completed transmission of the route information packet related to the primary queue 105, and in this case, The determination result is “Yes”. In step SB2, the packet generation unit 107 determines whether or not processing related to the secondary queue 106 is necessary. In this case, the determination result is “No” and the determination in step SB1 is performed. Thereafter, the packet generation unit 107 repeats the determinations of step SB1 and step SB2 until the determination result of step SB1 is “No” or the determination result of step SB2 is “Yes”.

Here, the processing relating to the secondary queue 106, preset time (e.g., provider edge router 20 _{time 1} of load becomes lower) and a preset condition (e.g., provider edge routers 20 ₁ of load threshold When the value is less than or equal to the value).

For example, when the route information packet 40 regarding the route information to be distributed is transmitted from the provider edge router 20 ₂ , the route information packet 40 is received by the route reflector device 100 ₄ . Here, the route information packet 40 includes information (label, etc. (weight, local preference, as path, origin, med, etc.) that affects the forwarding in the destination router (for example, provider edge router 20 ₁ in FIG. ₁ ). igpmetric)) and non-given information.

The route reflector device 100 ₄ copies the two route information packets 40a and the route information packet 40b from the route information packet 40, and transmits them. Route information packet 40a, after being relayed to route reflector apparatus 100 ₂ it is received by the route reflector apparatus 100 ₁ of the packet receiving unit 101 (see FIG. 2). On the other hand, the path information packet 40b after being relayed to a route reflector apparatus 100 _3, is received by the route reflector apparatus 100 ₁ of the packet receiving unit 101 (see FIG. 2).

As a result, the packet processing unit 102 of the route reflector device 100 ₁ sets “Yes” as a result of the determination made at step SA1 shown in FIG. In step SA2, the packet processing unit 102 stores the route information packet 40a and the route information packet 40b in the route information database 103, and then selects a route information packet corresponding to the optimum route from the route information packet 40a and the route information packet 40b. Select according to selection criteria.

  In this case, the packet processing unit 102 selects the route information packet 40 a as route information corresponding to the optimum route, and stores the route information packet 40 a in the optimum route information database 104. In step SA3, the packet processing unit 102 refers to the optimum route information database 104, and the route information packet 40a selected this time is the same as the previously selected route information packet stored in the optimum route information database 104. It is determined whether or not.

If the judgment result of step SA3 is "Yes", the packet processing unit 102 does not need to send the path information packet in the provider edge router 20 _1, without executing any processing, the determination in step SA1 Do.

As shown in FIG. 5, when a failure occurs in the route reflector device 100 ₂ , the packet processing unit 102 of the route reflector device 100 ₁ detects the failure via the packet receiving unit 101, and is shown in FIG. 3. The determination result of step SA1 is “Yes”.

At step SA2, the packet processing unit 102, selects previously the path information packet 40b received from the route reflector 100 ₃ from the routing information database 103, instead of the routing information packets 40a, as route information packet corresponding to the optimum route To do.

In step SA3, the packet processing unit 102 refers to the optimum route information database 104, and the currently selected route information packet 40b is the same as the previously selected route information packet stored in the optimum route information database 104. It is determined whether or not. In this case, since the transmission source of the route information packet 40a (route reflector device 100 ₂ ) and the transmission source of the route information packet 40b (route reflector device 100 ₃ ) viewed from the route reflector device 100 ₁ are different, the route information packet 40a. And the route information packet 40b are not the same. Therefore, the packet processing unit 102 sets “No” as a result of the determination made at step SA3.

In step SA4, the packet processing unit 102 affects the forwarding at the distribution destination of the route information packet (in this case, the provider edge router 20 ₁ ) for the selected route information packet 40b as compared with the route information packet 40a. Determine whether the information has changed.

In this case, assuming that the determination result is “No”, in step SA6, the packet processing unit 102 stores the route information packet 40b in the secondary queue 106 (see FIG. 2) as having low priority, and then performs step The determination of SA1 is performed. Therefore, the path information packet 40b until the determination in step SB2 shown in FIG. 4 is "Yes", not sent to the provider edge router 20 _1. If there is data relating to the same route in the secondary queue 106, the packet processing unit 102 rewrites the data into the route information packet 40b.

The preset time described above (e.g., the time when the load of the provider edge router 20 ₁ is lower) or a preset condition (e.g., when the load of the provider edge router 20 ₁ is equal to or less than the threshold value ), The packet generation unit 107 of the route reflector device 100 ₁ sets “Yes” as a result of the determination made at step SB2.

In step SB4, the packet generation unit 107 changes the destination of the route information packet 40b stored in the secondary queue 106, and generates a route information packet 40b for transmission. Next, the packet transmitting unit 108 transmits the path information packet 40b to the provider edge router 20 _1. Provider edge router 20 _1, when the load is low, that will receive a route information packet 40b, not a high load as described in FIG. 8.

  In one embodiment, the data amount of the route information packet that can be transmitted in step SB4 may be limited, and the route information packet 40b may be divided into a plurality of times and transmitted little by little.

  On the other hand, when the determination result of step SA4 shown in FIG. 3 is “Yes”, the packet processing unit 102 stores the route information packet in the primary queue 105 (see FIG. 2) as high priority, The determination at step SA1 is performed.

  Thereby, the packet generation unit 107 sets “No” as a result of the determination made at step SB1 shown in FIG. In step SB3, the packet generation unit 107 changes the destination of the route information packet stored in the primary queue 105, and generates a route information packet for transmission.

Next, the packet transmitting unit 108 transmits the path information packet to the provider edge router 20 _1. In this case, the provider edge router 20 _1, high priority route information packet to be sent immediately, there is no influence on forwarding those which may load the provider edge router 20 ₁ is high.

As described above, according to one embodiment, when receiving the path information packet to be relayed by the route reflector device 100 _1, based on predetermined criteria, the priority of the route information packet, the first priority Alternatively, when the second priority is determined to be lower than the first priority and the first priority is determined, the route information packet is stored in the primary queue 105, and when the second priority is determined, storing route information packet to the secondary queue 106, and sends to the destination provider edge router 20 ₁ routing information packets stored in the primary queue 105 immediately, the destination routing information packets stored in the secondary queue 106 Since transmission is performed at a timing that does not adversely affect the processing of the router, it is possible to reduce the load on the transmission destination of the route information packet.

  Although one embodiment according to the present invention has been described in detail with reference to the drawings, a specific configuration example is not limited to this one embodiment, and design changes and the like within a scope not departing from the gist of the present invention are possible. Even if it exists, it is included in this invention.

For example, in the above-described embodiment, a program for realizing each function of the route reflector devices 100 _{1 to} 100 ₄ is recorded on the computer-readable recording medium 300 shown in FIG. Each function may be realized by reading the recorded program into the computer 200 shown in FIG.

  A computer 200 shown in the figure includes a CPU (Central Processing Unit) 210 that executes the above-described program, an input device 220 such as a keyboard and a mouse, a ROM (Read Only Memory) 230 that stores various data, an operation parameter, and the like. RAM (Random Access Memory) 240, a reading device 250 for reading a program from the recording medium 300, and an output device 260 such as a display and a printer.

  The CPU 210 implements the above-described functions by reading a program recorded on the recording medium 300 via the reading device 250 and executing the program. Examples of the recording medium 300 include an optical disk, a flexible disk, and a hard disk.

  As described above, the packet relay device, the packet relay method, and the packet relay program according to the present invention are useful for relaying route information packets.

It is a block diagram which shows the structure of one Example concerning this invention. It is a block diagram showing the configuration of a route reflector apparatus 100 ₁ shown in FIG. 3 is a flowchart illustrating operations of a packet receiving unit 101 and a packet processing unit 102 illustrated in FIG. 3 is a flowchart illustrating operations of a packet generation unit 107 and a packet transmission unit 108 illustrated in FIG. It is a block diagram explaining operation | movement of the same Example. It is a block diagram which shows the structure of the modification of the same Example. It is a block diagram explaining the delivery method of the conventional route information. It is a block diagram explaining the delivery method of the conventional route information.

Explanation of symbols

100 _{1 to} 100 ₄ route reflector device 101 packet receiving unit 102 packet processing unit 103 route information database 104 optimum route information database 105 primary queue 106 secondary queue 107 packet generation unit 108 packet transmission unit

Claims (6)

A packet relay device that relays route information exchanged between routers in a packet network,
A first priority and a second priority lower than the first priority are provided, the route information transmitted to the destination router is compared with the received route information, and the forwarding of the router is affected. In some cases, priority determination means for determining the priority of the received route information as the first priority;
When it is determined that the priority is determined to be the first priority, the route information is stored in the first storage unit. When it is determined that the priority is the second priority, the route information is stored in the second storage unit. Control means;
The route information stored in the first storage unit is immediately transmitted to the destination router, and the route information stored in the second storage unit is transmitted at a timing that does not adversely affect the processing of the destination router. Transmission control means;
A packet relay device comprising: 2. The packet relay device according to claim 1 , wherein the transmission control unit transmits the path information when a load on the destination router is equal to or less than a threshold value. The packet relay apparatus according to claim 1 , wherein the transmission control unit transmits the route information in a plurality of times. A packet relay program applied to a packet relay device that relays route information exchanged between routers in a packet network,
On the computer,
A first priority and a second priority lower than the first priority are provided, the route information transmitted to the destination router is compared with the received route information, and the forwarding of the router is affected. A priority determination step of determining the priority of the received route information as the first priority in a case;
When it is determined that the priority is determined as the first priority in the priority determination step, the route information is stored in the first storage unit. When it is determined as the second priority, the route information is stored in the second storage unit. Control process;
The route information stored in the first storage unit is immediately transmitted to the destination router, and the route information stored in the second storage unit is transmitted at a timing that does not adversely affect the processing of the destination router. A transmission control process;
Packet relay program for executing 5. The packet relay program according to claim 4 , wherein, in the transmission control step, the route information is transmitted when a load on the destination router is equal to or less than a threshold value. 6. The packet relay program according to claim 4 , wherein, in the transmission control step, the route information is transmitted in a plurality of times.

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